Oligosaccharides such as inulin and various fructo-oligosaccharides are reported to promote the growth of bifido- and lacto-bacteria in the gastro-intestinal tract at the expense of pathogens such as Clostridium perfringens. For example, see Gibson et al; 1994; Food Microbiology, 11 (6), 491-498. Although most reported experimentation has been carried out in vitro, there have been reports that these oligosaccharides have a similar effect in the gut of rats and humans. Further, promoting the growth of bifido- and lacto-bacteria through the use of oligosaccharides is reported to have various beneficial effects on animals and humans. These beneficial effects include the prevention or treatment of diarrhea, and increased growth; improved ability to breed, and enhanced health.
These beneficial effects have resulted in use of oligosaccharides, particularly fructo-oligosaccharides, in human foods and feeds for live stock. For example, International patent application WO 94/27617 discloses the use of a caramel which contains fructo-oligosaccharides in animal feed to enhance the health of live stock. However, reports of the use of inulin also exist. For example Japanese patent application 63-309147 discloses the use of a purified inulin in the feed for younger animals to prevent diarrhea after weaning and to increase body weight. Similarly, U.S. Pat. No. 4,865,852 discloses the use of inulin in the form of treated chicory as a feed for live stock.
Although the primary focus for oligosaccharides has been human foods and feeds for live stock, the use of fructo-oligosaccharides in a veterinary diet for pets has also been suggested (Willard et al; 1994, Am. J. Vet. Res., 55, 654-659). Further, products containing fructo-oligosaccharide are on the market; for example the Eukanuba product (The IAMS Company).
For the products which contain inulin, the inulin is usually purified from plants which contain higher concentrations of inulin; such as chicory, Jerusalem artichoke, leek and asparagus. Otherwise, the plant material is treated in some form or another prior to use. A reason for the purification or treatment is that the plants themselves are reported to have bitter flavors which result in palatability problems; see for example U.S. Pat. No. 4,865,852. This is particularly the case with chicory where the bitter flavors are believed to be due to the concentrations of sesquiterpene lactones such as lactucin and lactucopicrin in chicory. Also, it is generally believed that more accurate control of the amounts added may be obtained with purified product. Various procedures for purifying the inulin or treating the plant material have been reported. Usually however they include the steps of chopping up the plant, extracting it, and hydrolyzing it with acids or enzymes. The hydrolysate is then collected and condensed to obtain the inulin. For example, Japanese patent application 63-309147 discloses grinding chicory tubers, partially hydrolyzing them with acids, and then drying the hydrolysate with or without neutralization.
Unfortunately, fructo-oligosaccharides and purified inulin greatly add to the cost of the products. Consequently, for pet foods, their use has been confined to specialty veterinary products such as the Eukanuba product and to pet treats. Similarly, for human foods, their use has been confined to specialty products.
Therefore there is a need for a cereal product which has the properties of food which contains fructo-oligosaccharides and purified inulin, which is palatable to humans and animals, and which may be inexpensively produced.